[llvm] [AMDGPU] Support alloca in AS0 (PR #136584)

[Shilei Tian via llvm-commits]

shiltian wrote:

> The logic to detect private->flat casts also needs to be updated in AMDGPUAttributor

You mean in the `AAAddressSpace`?

https://github.com/llvm/llvm-project/pull/136584